Automatic electric tractor guide



Feb. 7, 1950 w. c. JENKINS AUTOMATIC ELECTRIC TRACTOR cum:

4 Sheets-Sheet 1 Filed-Feb. 11, 1949 INVENTOR.

w/u MM c'. JENKINS,

BY W-WW-Moz Feb. 7, 1950 w. c. JENKINS 2,496,727

AUTOMATIC ELECTRIC TRACTOR GUIDE Filed'Feb. 11, 1949 4 Sheets-Sheet 2 mu /AM a. JE/VK/NS,

BY WWflmwz M0:

ATTOE/VE Y5:

Feb. 7, 1950 7 w. c. JENKINS 2,496,727

AUTOMATIC ELECTRIC TRACTOR GUIDE Filed Feb. 11, 1949 I 4 Sheets-Sheet 3 IN VEN TOR. WILL IAM C. JEN/(INS,

ATTORNEY-5'.

Feb. 7, 1950 w. c. JENKINS 2,496,727

'AUTOM ATIC ELECTRIC TRACTOR GUIDE Filed Feb. 11, 1949 4 Sheets-Sheet 4 FIG. 15.

v INVENTOR. WILL/4M c. JENK/NS,

v lentines. 1, 1950 UNITED STATES PATENT OFFICE 2,426,727 AUTOMATIC Emc'rarc 'raAo'ron GUIDE William C. Jenkins, Inglewood, Calif.

Application February 11, 1949, Serial No. 75,192

Claims. (Cl. sis-28s) This invention relates to automatic steering devices fcr tractors, and more particularly to an automatic tractor steering device which is electrically operated.

A main object of the invention is to provide a novel and improved guide device for a tractor, which is very simple in construction, easy to install and readily adjustable to suit various operating conditions of the tractor.

A further object of the invention is to provide an improved guide means readily attachable to a tractor and having various quickly operable adjustment means whereby the guide means may be adjusted to suit the work being performed b the tractor, the guiding element thereof travelling in the ground beside the tractor and having electrical circuit controlling elements which respond to deviations of the tractor from its intended course to correct the steering of the tractor so that it is held to said intended course.

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

Figure 1 is a side elevational view of a tractor provided with an automatic guide device constructed in accordance with the present invention;

Figure 2 is an enlarged cross-sectional detail I view taken on line 2-2 of Figure l and showing the ground-engaging deviation-responsive element of the guide device;

Figure 3 is a cross-sectional detail view taken on line H oi'Figure 2;

Figure 4 is an enlarged cross-sectional detail view taken on line 4-4 of Figure 2;

Figure 5 is a fragmentary cross-sectional detail view taken on line 5-! of Figure 2;

Figure 6 is an elevational detail view partly in cross-section, taken on line 0-4 of Figure 2;

Figure '7 is an enlarged cross-sectional detail view taken on line l| of Figure 6;

Figure 8 is an enlarged cross-sectional detail view taken on line 0-8 of Fi ure 6;

Figure 9 is an enlarged cross-sectional detail view taken on line 9-! of Figure 6;

Figure 10 is an enlarged perspective detail view of the terminal panelof the guide device of FIE- ure 1;

Figure 11 is an enlarged fragmentary elevationai detail view of the adjustable connecting link member employed in the guide device of Figure 1 for operating the elevating means for the guide device from the tractor power take-oi!- 'member 25.

2 Figure 12 is an enlarged cross-sectional detail view taken on line l2-l 2 of Figure 1, showing the electric motor employed for automatically steering the tractor;

Figure 13 is a top plan view of a guide shoe member which may be employed with the guide .device of Figure 1 in place of the disc element shown therein;

Figure 14 is a side elevational view of the shoe member of Figure 13;

Figure 15 is a schematic wiring diagram of the electrical circuit employed in the guide device of Figure 1.

Referring to the drawings, 1 I designates a conventional tractor having the steerable front wheels l2. The front wheels are manually steered by means of a steerin post l3 rotatably supported on the tractor frame by means of brackets such as H. Post l3 has at its forward end a worm i5 engaging a worm gear mounted on the vertical steering shaft [6, which is connected to the front wheelaxle. At its rear end, post I! is provided with a steering wheel ll.

Mounted on the tractor adjacent the intermediate portion of steering post I: is a reversible electric motor It. The shaft of motor It carries a worm is meshing with a worm gear 20 secured to post II. As shown in Figure 12, worm gear 2. may comprise two segments clamped together, whereby the assemblyof said worm gear on the intermediate portion of post It is facilitated.

Secured to one of the longitudinal side beams 2| of the tractor frame, and projecting laterally therefrom is a channelbeam 22. Nested within channel beam 22 and secured thereto in an adjusted outwardly projecting position is another channel beam 23. Secured to the end of beam 23 and angularly adjustable with respect thereto is a bracket member 24 carrying a vertical sleeve member 24 is secured to the web of channel sleeve member 29 with respect to the outer sleeve member 25. Inner sleeve member 29 has a squared bore in which is siidably positioned a squared shaft 82. Shaft 32 is provided adjacent its top end with a collar 23 limiting upward As shown in Figure 2, the bracket I movement of sleeve with respect to shaft 52. Secured to the lower end of shaft 32 is an enlarged head or abutment 54. Encircling the lower portion of shaft 32 and bearing between flange 3| and abutment 34 is a heavy coiled spring 35 biasing shaft 32 downwardly with respect to sleeve member 25. Said sleeve member 28 is formed with rack teeth 35, and meshing with said teeth is a gear 31 projecting through a slot 35 formed in vertical sleeve member 25. Gear 31 is carried on a shaft 39 rotatively mounted on upstanding brackets and 4| secured to the respective channel members 23 and 22. Secured to the inner end of shaft 59 is a lever 42. Designated at 45 is an upstanding toothed sector plate secured to channel member 22 adjacent lever 42, through which the end of shaft 33 is rotatively received. Lever 42 is provided with a slidable locking bar 44 engageable with the teeth of sector plate 43 to lock the shaft 35 in a fixed position. Pivoted to the upper end of lever 42 is a handle 45 connected to bar 44 for releasing said bar from engagement with plate 43 when it is desired to rotate shaft 35. The upper end of lever 42 is provided with a pivoted ball 45 engageable over handle 45 to hold bar 44 in a retracted position. Rotation of shaft 55 in one direction lowers sleeve member 29 and rotation of said shaft in the opposit direction raises said sleeve member. The sleeve member may be locked in an adjusted position by engaging the locking bar 44 with the toothed sector plate 43.

Lever 42 provides a means of manually rotating shaft 39 to obtain a desired vertical adjustment of the position of sleeve member 25. When it is desired to elevate said sleeve member and squared shaft 32 to raise the parts carried by said shaft 32 to an inoperative position, the power take-off shaft of the tractor may be utilized to provide the required torque on shaft 59. For this purpose, an arm 41 is secured to shaft 39. Pivotally connected to the end of arm 41 is a rearwardly extending tubular rod 45. Connected to the power take-off shaft of the tractor, not shown, is an arm 49. Pivotally connected to the end of arm 45 is a bar 5|! extending slidably into tubular rod 45. Bar is formed with a plurality of spaced notches 5|. Pivoted on tubular rod 48 is a dog 52 engageable through an opening in rod 45 with the bar 50 and biased into engaging relation therewith by a spring 53. Rod 48 is provided with a pivoted bail 54 engageable over dog 52 to hold said dog out of engagement with the bar 55. When bail 45 is engaged over handle 45 to hold bar 44 in retracted position and dog 52 is disengaged from ball 54, dog 52 engages one of the notches 5| in bar 55, whereby torque may be transmitted from the power takeofl shaft of the tractor to shaft 39 through arm 49, bar 50, rod 45 and arm 41. However, during normal use of the automatic steerin device, dog 52 is held by ball 54 in a non-engaging position with respect to bar 55 and rod 45 may slide freely with respect to said bar.

Referring now to Figures 2 and 6, it will be seen that secured to opposite sides of the abutment 34 are respective inclined plate members 55, 55 having the depending vertical portions 51 and 55. Said vertical portions terminate in horizontal flanges 55 and 55. Secured to the respective flanges 59 and 55 are the longitudinally extending elongated rectangular frames 5| and 52. The upper longitudinal element of frame 52 has a depending central rib 53 and the lower longitudinal element thereof has an upstanding central rib 54. Th forward and rear ends of the longitudinal frames 5| and 52 are connected by transverse plate members 55 and 55. Slidably positioned in the intermediate portion of frame 52 is a block member 51 formed at its top and bottom with longitudinal grooves slidably receiving the respective opposing longitudinal ribs 53 54. Rigidly secured in the intermediate portion of frame 5| is another block member 51'. Each block member is formed with a spherical seat 55 in which is positioned a ball bearing assembly 55 having universal pivotal cooperation with the seat 55. Designated at 15, 15 are respective shaft elements whose outer ends are journalled in the respective ball-bearing assemblies 55. The inner ends of the shaft elements are provided with flanges, shown at 1|. 1| and secured between said flanges. coaxiallywith the shaft elements 15, 15 is a disc member 12. a

The block member 51 has secured to its forward and rear ends the respective pairs of longitudinally-extending guide pins 15, 15 and 14, 14. Slidably positioned in the frame 52 forwardly and rearwardly of the block member 51 are the abutment blocks 15 and 15 formed with longitudinal bores, such as shown at 11, slidably receiving the respective pairs of pins 15, 15 and 14, 14. Encircling the respective pins are coiled springs 15. Threaded through the forward and rear ends of the frame 52 are respective screw members 15 and 55 engaging the respective abutment blocks 15 and 15, whereby said abutment blocks may be adjusted inwardly or outwardly with respect to the block member 51. The springs 15 normally maintain the block member 51 longitudinally centered between the abutment blocks 15 and 15. Disc member 12 may be thus ad- Justed to extend in a longitudinal plane parallel to the desired plane of movement of the tractor, and penetrates the soil along side the tractor at a sumcient depth to hold it from turning out of said longitudinal plane. When the tractor deviates from its desired direction, the vertical side plates 51, 55, swing with the tractor, carrying with them the parallel frames 5|, 52. Since the disc member 12 remains undeviated, the block member 51 moves away from its normal positions in the frame 52.

As shown in Figure 6, the top element of frame 52 is provided adjacent the front and rear ends of the block member 51 with respective electrical contacts 5| and 52, suitably insulated from the frame. Block member 51 carries contacts 55 and 54 opposite the respective contacts 5| and 52 and normally spaced therefrom. When the tractor swings in one direction from its desired course, contact 5| engages contact 53. When the tractor swings in the opposite direction from its desired course, contact 52 engages contact 54. The contacts 5|, 55 and 52, 54 are employed to control the energizing circuits for the reversible steering motor l5.

Referring now to Figure 15, it will be seen that 55 designates a storage battery carried by the tractor, the negative terminal of which is connected to a ground wire 55. The motor I! may be any conventional type of reversing motor and is shown by way of example as having the two reversely wound series fields 51, 55. One armature terminal of the motor is grounded. The other armature terminal is connected to a common connection of the series fields, shown at 55. Designated at 55 and 5| are respective solenoids.

Solenoid has an armature 82 engageable with a contact 98 responsive to energization of the solenoid. Solenoid 9| has an armature 84 engageable with a contact 85 responsive to energization of solenoid 9|. Designated at 88 is a wire connecting one terminal of solenoid 80 and of solenoid 9| to the positive terminal of battery 85. The armatures 92 and 94 are connected by respective wires 91 and 98 to the wire 86 connected to the positive terminal of battery 85. Contact 93 is connected to field winding 81 and contact 95 is connected to field winding 88. Designated at 99 and I00 are respective female jacks carried on a panel I02, mounted on the tractor adjacent the operators seat. The remaining terminal of solenoid 90 is connected by a wire I03 to jack 89. The remaining terminal of solenoid 9| is connected by a wire I04 to jack I00. Contact 8| is connected by a wire I to a male plug I06 received in jack IIIIJ. ,Contact 82 is connected by a wire I01 to a v le plug I08 received in jack 99. Contact 83 is connected to contact-84 by a wire I09, and wire T09 is connected by a wire 0 to ground. It will hei -seen that when contact 8| engages contact 83,

solenoid 9| will become energized through a circuit comprising ground wire 86, battery 85, wire 86, the solenoid winding, wire I04, jack I00, plug I06, wire I05, contacts 83 and 8|, wire I09, wire I I0 and ground. This causes armature 94 to engage contact 95 and energizes motor I8 through series field 88 through a circuit comprising wire 86, battery 85, wire 86, wire 98, armature 94, contact 95, series field 88, the motor armature, and ground. The motor operates in a direction causing steering post I3 to turn the wheels I2 of the tractor in the proper direction to remove the reacting torque on disc 12, that is, to steer the tractor so that it travels parallel to disc 12. When this occurs, contact 8| disengages from contact 83, deenergizing solenoid 9| and deenergizing motor I8 as soon as armature 94 disengages from contact 95.

Similarly, when contact 82 engages contact 84, solenoid 90 becomes energized through a circuit comprising ground wire 86, battery 85, wire 96, the solenoid winding, wire I03, jack 99, plug I08, wire I01, contact 82, contact 84, wire I09, wire IIO, and ground. This raises armature 92 and energizes motor I8 through series field 81, causing the motor to turn post I3 in the proper direction to steer the tractor back to the direction of travel of disc 12. When the tractor has been restored to this direction, the motor becomes deenergized by the opening of contacts 82, 84 and the consequent deenergization of solenoid 80.

The steering solenoids 90 and 9| may be energized manually, by the provision of push button switches H2 and H3 mounted on the panel I02. The switches H2 and H3 have respective contacts 4 and 5 which are connected together by a wire II6, said wire II6 being grounded. The remaining contact II1v of switch H2 is connected by a wire II8 to jack 99. The

remaining contact II9 of switch H3 is connected by a wire I20 to jack I00. Closure of switch II2 bridges contacts I I1 and I I4, producing the same effect as closure of contacts 82 and 84. Closure of switch II3 bridges contacts 9 and H5, producing the same effect as closure of contacts 8|, 83. r v

From Figure 2, it will be seen that spring 35 exerts a downward biasing force on abutment 34 which is transmitted to disc 12 through plate members 55, 56, vertical arms 51, 58, frames BI, 62, the bearing blocks 81 therein, the respective universal bearings, and the shaft elements 10, 10. The magnitude of this downward biasing force depends upon the adjusted position of the sleeve member 28. Therefore the depth of penetration of disc member 12 into the soil adjacent the tractor may be regulated by adjusting the hand lever 42.

As previously pointed out, the shaft 32 and the parts carried thereby may be elevated to inoperative positions from the power take-off shaft of the tractor-by engaging dog 52 with the notched bar 50 and at the same time holding bar 44 in a retracted position by means of bail 48.

The disc 12 is employed as the deviation-sensitive member when the tractor is employed for fiat farming such as sowing grain, discing, harrowing, laying off row crops, planting row crops, and for various other operations where no furrows are present. Where furrows are present and the tractor must be guided parallel to the furrows, the disc 12 is replaced by the furrow attachment shown in Figures 13 and 14. Said attachment comprises a shoe member I2I of generally channel shape having the top wall I22 and the forwardly convergent depending side walls I23, I23. Secured to top wall I22 is a bracket I24 having an upstanding longitudinal central web I25. When the attachment of Figures 13 and 14 is to be employed, the web I25 is secured between the flanges 1|, 1| provided at the inner ends of the shaft elements I0, 10 the web I25 replacing the disc 12. The shoe member I2| is positioned in a furrow parallel to the intended path of movement of the tractor, the hand lever 42 being adjusted to provide a suitable amount of downward force on the shoe member to maintain it in said furrow. Deviations of the tractor will then be corrected by closure of either the contacts 8|, 83 or 84, 82 caused by swinging of the frames GI, 62 with respect to the shaft elements 10, in the same manner as previously described.

The furrow attachment shown in Figures 13 and 14 may be employed in various ways. For example, it may be employed in cultivating row crops, where furrows are initially present, until the furrows are filled. It may then be removed and replaced by the disc 12 for the remainder of the cultivating operation.

The guide device eliminates the need for human guidance of the tractor while it is moving along its desired course and allows the operator to perform other duties during the movement of the tractor. This greatly reduces the number of men required to perform various operations for which the tractor is employed, since a driver is required on the tractor only at times when the tractor is to be turned from its preset course.

While specific embodiments of automatic guide apparatus for a tractor have been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims.

What is claimed is:

1. In a tractor, a steering shaft, an electric motor coupled to said steering shaft, bracket means secured to the tractor frame, a ground- I engaging member movably secured to said bracket means, said ground-engaging member being oriented in a plane parallel to the intended ion- .gitudinal plane of movement of the tractor and engaging the soil at a substantial depth so that it resists turning movement, a pair of normally open contacts, one of said contacts being carried by said bracket means and the other contact being mechanically connected to .said ground-engaging member, said contacts being engageable responsive to deviation of the tractor from its intended longitudinal plane of movement, and an energizing circuit, including said contacts, connected to said electric motor.

2. In a tractor, a steering shaft, a reversible electric motor coupled to said' steering shaft, bracket means secured to the tractor frame, a ground-engaging member swivelly secured to said bracket means, spring means biasing said ground-engaging member toward parallelism with the tractor, means exerting a downward force on said ground-engaging means and holding said ground-engaging means at a substantial depth below ground level so that it resists turning movement, respective energizing circuits associated with said motor for operating it in opposite directions, and a reversing switch controlled by relative angling movement of said groundengaging means and bracket means and selectively connecting one or the other of said energizing circuits to the electric motor responsive to said angling movement.

3. In a tractor, a steering shaft, a reversible electric motor coupled to said steering shaft, bracket means secured to the tractor frame, a ground-engaging member swivelly secured to said bracket means, spring means biasing said ground-engaging member toward parallelism with the tractor, adjustable means exerting a downward force on said ground-engaging means and urging said ground-engaging means toward a substantial depth of ground engagement so that said ground-engaging means resists turning movement, a first contact element mechanically connected to said ground-engaging means, re-

spective opposing contact elements on said bracket means on opposite sides of said first contact element and movable into contact with the first contact element responsive to deviation of the tractor from parallelism with the ground-engaging means, and respective reversing circuits connected to said motor, each circuit including said first contact element and one of the opposing contact elements.

4. In a tractor, a steering shaft, a reversible tractor frame. a, vertically adjustable support carried at the end of said bracket means. said support comprising spaced longitudinal vertical frames, yoke arms secured to said frames, and a vertical shaft secured to said arms and received in said bracket means, spring means biasing the support downwardly, a shaft member slidably carried in said frames, spring means biasing said shaft member toward a position substantially transverse to the frames, a ground-engaging member secured transversely to said shaft member, a first contact element carried by said shaft member adjacent one of the longitudinal frames, respective opposing contact elements on said one frame on opposite sides of said first contact element and movable selectively into contact with said first element responsive to deviation of the tractor from parallelism with the groundengaging member. and respective reversing circuits connected to said motor, each circuit including said first contact element and one of the opposing contact elements.

5. In a tractor, a steering shaft, a reversible electric motor coupled to said steering shaft, laterally-extending bracket means secured to the tractor frame, a vertical sleeve carried at the end of said bracket means, means for adjusting the sleeve vertically with respect to said bracket means, a non-circular vertical shaft slidably carried in said sleeve, spring means biasing the vertical shaft downwardly with respect to the sleeve, opposed yoke arms secured to the lower end of the vertical shaft, respective elongated longitudinal frames secured to the lower ends of the yoke arms, respective journal blocks slidably carried in the elongated frames, bearings pivotally mounted in said journal blocks, spring means biasing the journal blocks toward intermediate positions in said elongated frames, a transverse shaft element journalled in said bearings, a ground-engaging member secured transversely to said shaft element, a first contact element carried by one of the journal blocks adjacent a longitudinal arm of one of the elongated frames, respective opposing contact elements on said longitudinal arm on opposite sides of said first contact element and movable selectively into contact therewith responsive to deviation of the tractor from parallelism with the ground-engaging member, and respective reversing circuits connected to said motor, each circuit including said first contact element and one of the opposing contact elements.

WILLIAM C. JENKINS.

No references cited. 

